scholarly journals 1,6-Dehydropinidine Is an Abundant Compound in Picea abies (Pinaceae) Sprouts and 1,6-Dehydropinidine Fraction Shows Antibacterial Activity against Streptococcus equi Subsp. equi

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4558
Author(s):  
Virpi Virjamo ◽  
Pia Fyhrquist ◽  
Akseli Koskinen ◽  
Anu Lavola ◽  
Katri Nissinen ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Picea Abies ◽  
Solid Phase ◽  
Antibacterial Properties ◽  
Model Organism ◽  
Phase Partitioning ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Streptococcus Equi ◽  
Full Picture

Knowledge about the defensive chemistry of coniferous trees has increased in recent years regarding a number of alkaloid compounds; in addition to phenolics and terpenes. Here, we show that Norway spruce (Picea abies (L.) H. Karst.), an important boreal zone tree species; accumulates 1,6-dehydropinidine (2-methyl-6-(2-propenyl)-1,6-piperideine) in its needles and bark. We reanalyzed previously published GC-MS data to obtain a full picture of 1,6-dehydropinidine in P. abies. 1,6-dehydropinidine appeared to especially accumulate in developing spring shoots. We used solid-phase partitioning to collect the alkaloid fraction of the sprouts and thin-layer chromatography to purify 1,6-dehydropinidine. The antibacterial properties of the 1,6-dehydropinidine fraction were tested using a broth microdilution method; with Streptococcus equi subsp. equi as a model organism. Based on our results 1,6-dehydropinidine is common in alkaloid extractions from P. abies (0.4 ± 0.03 mg g−1 dw in mature needles) and it is especially abundant in young spruce shoots (2.7 ± 0.5 mg g−1 dw). Moreover; 1,6-dehydropinidine extracted from P. abies sprouts showed mild antibacterial potential against Streptococcus equi subsp. equi (MIC 55 µg mL−1). The antibacterial activity of a plant compound thought of as an intermediate rather than an end-product of biosynthesis calls for more detailed studies regarding the biological function of these coniferous alkaloids

Synthesis and Antibacterial Activities of Amidine Substituted Monocyclic β-Lactams

2021 ◽  
Vol 17 ◽  
Author(s):  
Lijuan Zhai ◽  
Lili He ◽  
Yuanbai Liu ◽  
Ko Ko Myo ◽  
Zafar Iqbal ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Species ◽  
Antimicrobial Effect ◽  
Antibacterial Activities ◽  
Lead Target ◽  
Bacterial Strains ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Clinical Interest

Background: Mononcyclic β-lactams are regarded as the most resistant class of β-lactams against a series of β-lactamases though possess limited antibacterial activity. Aztreonam being the first clinically approved monobactam needs broad-spectrum efficacy through structural modification. Objective: We strive to synthesize a number of monocyclic β-lactams by varying the substituents at N1, C3 and C4 positions of azetidinone ring and study the antimicrobial effect on variable bacterial strains. Methods: Seven new monobactam derivatives 23a-g, containing substituted-amidine moieties linked to the azetidinone ring via thiazole linker, were synthesized through multistep synthesis. The final compounds were investigated for their in vitro antibacterial activities using broth microdilution method, against ten bacterial strains of clinical interest. The minimum inhibitory concentrations (MICs) of newly synthesized derivatives were compared with aztreonam, ceftazidime and meropenem, existing clinical antibiotics. Results: All compounds 23a-g showed higher antibacterial activities (MIC 0.25 µg/mL to 64 µg/mL) against tested strains as compared to aztreonam (MIC 16 µg/mL to >64 µg/mL) and ceftazidime (MIC >64 µg/mL). However all compounds, except 23d, exhibited lower antibacterial activity against all tested bacterial strains as compared to meropenem. Conclusion: Compound 23d showed comparable or improved antibacterial activity (MIC 0.25 µg/mL to 2 µg/mL) to meropenem (MIC 1 µg/mL to 2 µg/mL) in case of seven bacterial species. Therefore, compound 23d may be valuable lead target for further investigations against multi-drug resistant Gram-negative bacteria.

scholarly journals Antibacterial Triterpenoids from the Bark of Sonneratia alba (Lythraceae)

2015 ◽  
Vol 10 (2) ◽  
pp. 1934578X1501000
Author(s):  
Harizon ◽  
Betry Pujiastuti ◽  
Dikdik Kurnia ◽  
Dadan Sumiarsa ◽  
Yoshihito Shiono ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Mass Spectrometric ◽  
Broth Microdilution ◽  
Mass Spectrometric Data ◽  
Spectrometric Data ◽  
Gram Positive Bacteria ◽  
Microdilution Method ◽  
Sonneratia Alba ◽  
Broth Microdilution Method

The new lupane-type triterpenoid, 3β-hydroxy-lup-9(11), 12-diene, 28-oic acid (1), along with two known lupane-type triterpenoids, lupeol (2) and lupan-3p-ol (3), were isolated from the bark of Sonnetaria alba. The structure of the new compound was elucidated on the basis of spectroscopic and mass spectrometric data analysis. Using the broth microdilution method, all compounds exhibited antibacterial activity against the Gram-positive bacteria Staphylococcus aureus ATCC 6538 and Streptococcus mutans ATCC 25175, with minimum inhibitory concentrations ranging from 15-33 to 35-55 ng/mL, respectively.

scholarly journals Antibacterial Activity of the Essential Oil of Heracleum Sibiricum

2013 ◽  
Vol 8 (9) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Dragoljub L. Miladinović ◽  
Budimir S. Ilić ◽  
Tatjana M. Mihajilov-Krstev ◽  
Dejan M. Nikolić ◽  
Olga G. Cvetković ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Essential Oil ◽  
Antimicrobial Activities ◽  
Bacterial Strains ◽  
Gram Positive Bacteria ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Major Chemical ◽  
Total Oil ◽  
Chemical Class

The composition and antimicrobial activity of the essential oil of Heracleum sibiricum L. (Apiaceae) was studied. The aerial part of plant was hydro-distilled and chemical composition of the essential oil was analyzed by GC and GC-MS. Forty-six compounds, corresponding to 95.12% of the total oil, were identified. Esters represented the major chemical class (69.55%) while the main constituents were octyl butanoate (36.82%), hexyl butanoate (16.08%), 1-octanol (13.62%) and octyl hexanoate (8.10%). Antibacterial activity of the essential oil and reference antibiotics against nine bacterial strains was tested by the broth microdilution method. The results of the bioassays showed that essential oil had slight antimicrobial activities against all tested microorganisms (MIC and MBC values were in the range of 2431.2 to 9724.8 μg/mL). Reference antibiotics were active in concentrations between 0.5 and 16.0 μg/mL. The results confirm that Gram-positive bacteria were more susceptible to the essential oil of H. sibiricum, in comparison with Gram-negative bacteria.

scholarly journals Synthesis andIn VitroEvaluation of New Thiosemicarbazone Derivatives as Potential Antimicrobial Agents

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Zafer Asım Kaplancıklı ◽  
Mehlika Dilek Altıntop ◽  
Belgin Sever ◽  
Zerrin Cantürk ◽  
Ahmet Özdemir
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Aromatic Aldehydes ◽  
Antitubercular Activity ◽  
Alamar Blue Assay ◽  
Alamar Blue ◽  
Inhibitory Effects ◽  
Microdilution Method ◽  
Broth Microdilution Method

In an effort to develop potent antimicrobial agents, new thiosemicarbazone derivatives were synthesizedviathe reaction of 4-[4-(trifluoromethyl)phenyl]thiosemicarbazide with aromatic aldehydes. The compounds were evaluated for their inhibitory effects on pathogenic bacteria and yeasts using the CLSI broth microdilution method. Microplate Alamar Blue Assay was also carried out to determine the antimycobacterial activities of the compounds againstMycobacterium tuberculosisH37Rv. Among these derivatives, compounds5and11were more effective againstEnterococcus faecalis(ATCC 29212) than chloramphenicol, whereas compounds1,2, and12and chloramphenicol showed the same level of antibacterial activity againstE. faecalis. Moreover, compound2and chloramphenicol exhibited the same level of antibacterial activity againstStaphylococcus aureus. On the other hand, the most potent anticandidal derivatives were found as compounds2and5. These derivatives and ketoconazole exhibited the same level of antifungal activity againstCandida glabrata. According to the Microplate Alamar Blue Assay, the tested compounds showed weak to moderate antitubercular activity.

scholarly journals Antibacterial Activity of Antibiotic-Impregnated Bone Cement Based Coatings Against Microorganisms with Different Antibiotic Resistance Levels

2018 ◽  
Vol 24 (4) ◽  
pp. 105-110
Author(s):  
D. V. Tapalski ◽  
P. A. Volotovski ◽  
A. I. Kozlova ◽  
A. Sitnik
Keyword(s):  
Antibacterial Activity ◽  
Bone Cement ◽  
Antibiotic Activity ◽  
Broth Microdilution ◽  
Antibiotic Resistant ◽  
Microdilution Method ◽  
Bactericidal Properties ◽  
Broth Microdilution Method ◽  
Marked Activity ◽  
Agar Method

Purpose — to evaluate the presence and duration of antibiotic activity of antibiotic-impregnated bone cement based coatings samples against antibiotic-sensitive and antibiotic-resistant microorganisms.Material and Methods. Bone cement based coatings impregnated with antibiotics (gentamycin, vancomycin, colistin, meropenem, fosfomycin) are formed on titanium (Ti) plates. A plate rinse was carried out; antibiotic concentrations in the rinsed solutions were estimated by a serial broth microdilution method. Antibacterial activity of the control and rinsed samples against the antibiotic-sensitive and multiple-antibiotic-resistant Staphylococcus aureus and Pseudomonas aeruginosa strains was estimated by a bilayer agar method.Results. The meropenem and fosfomycin concentrations in the rinsed solutions obtained at a one-fold (16 μg/ml for both antibiotics) and two-fold treatment (2 μg/ml for meropenem and 8 μg/ml for fosfomycin) were sufficient to suppress the growth of the control strains. One-fold rinse of samples with colistin eliminated their antibacterial activity completely. The marked activity of the samples with meropenem and fosfomycin persisted against the antibiotic-sensitive P. aeruginosa ATCC 27853 strain after 2 rinse cycles; single-rinsed samples with fosfomycin also maintained the activity against the extensively antibioticresistant P. aeruginosa BP-150 strain. Vancomycin-containing samples possessed the sufficient antibacterial activity against both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) S. aureus strains; two-fold rinse of the samples eliminated their bactericidal properties.Conclusion. Bone cement based coatings impregnated with fosfomycin and meropenem possess the most marked and long-lasting antibacterial activity, manifested mainly against the antibiotic-sensitive strains. 

scholarly journals Semi-bionic Extraction Process and Antibacterial Activity against Salmonella goose of Compound Chinese Medicine Dahuang Qinyu San

2021 ◽  
Vol 71 (2) ◽  
Author(s):  
Hatungimana Françoise ◽  
Hongjun Wang
Keyword(s):  
Antibacterial Activity ◽  
Ph Value ◽  
Design Method ◽  
Uniform Design ◽  
Extraction Process ◽  
Chinese Herbs ◽  
Optimal Conditions ◽  
Liquid Ratio ◽  
Microdilution Method ◽  
Broth Microdilution Method

Various classical Chinese medicines have shown their efficiency in curing various infectious diseases. Among them, Dahuang Qinyu San (DQS) found in the Chinese Veterinary Pharmacopoeia is composed of three kinds of Chinese herbs: rhubarb, Scutellaria baicalensis, and Outtuynia cordata. Due to its urgent need in human health and its effectiveness, a semi-bionic extract of Dahuang Qinyu San (SEDQS) was studied to evaluate its optimal extraction conditions and investigate its antibacterial activity against Salmonella goose. The U5 (53) uniform design method was used to investigate the effects of three independent variables, including pH value (X1), solid-to-liquid ratio (X2), and extraction time (X3), on the composite score (Y) of the extract rate and the MIC, using the semi-bionic extraction process. The broth microdilution method was also used to determine the minimum inhibitory concentration (MIC) against Salmonella goose. After 30 minutes of extraction, the optimal conditions for SEDQS were found to be pH 8.3 and a solidto-liquid ratio of 1: 40. Under these optimal conditions, the extraction rate was 43.66 % and the MIC was 9.10 mg/ml, which indicates antibacterial efficacy against Salmonella goose.

scholarly journals Chemical Composition, and Evaluation of Antibacterial，Antibiofilm and Synergistic Effects with Conventional Antibiotics of Essential Oil from Mallotus repandus

2021 ◽  
Vol 15 (4) ◽  
pp. 324-329
Author(s):  
Pengxiang Lai ◽  
Xin-Chen Zhang ◽  
Lin Zhu ◽  
Xin-Yu Li ◽  
Li-Chuan Liu
Keyword(s):  
Essential Oil ◽  
Biofilm Formation ◽  
Synergistic Effects ◽  
Antibacterial Properties ◽  
Good Alternative ◽  
Bactericidal Effect ◽  
Bacterial Strains ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Mallotus Repandus

The essential oil (EO) of aerial parts of Mallotus repandus (Willd.) Muell. Arg. was extracted by hydrodistillation and characterized by GC/FID and GC/MS. Fifty-one compounds comprising 97.1% of the EO were identified, of which α-humulene (18.7%), β-selinene (12.8%), aciphyllene (10.7%), (E)-caryophyllene (8.4%), α-copaene (5.5%), humulene epoxide II (4.9%) and caryophyllene oxide (4.3%) were the major compounds. The EO was evaluated for antibacterial properties using broth microdilution method and crystal-violet static biofilm formation assay. The M. repandus EO possessed a bactericidal effect against tested gram-positive bacteria strains (MIC = MBC: 0.05-0.10 mg/mL). Further, the EO showed the ability to inhibit the biofilm formation of Staphylococcus aureus. In addition, the potential synergistic effect was assessed by checkerboard method. Combination of the M. repandus EO with Streptomycin showed synergistic effects against the tested bacterial strains. This study demonstrates that M. repandus EO could be further explored as good alternative for potential pharmaceuticals.

scholarly journals Identification of Substances Produced by Cercospora brachiata in Absence of Light and Evaluation of Antibacterial Activity

2021 ◽  
Vol 7 (9) ◽  
pp. 680
Author(s):  
John K. R. P. Felisbino ◽  
Bruno S. Vieira ◽  
Alberto de Oliveira ◽  
Neiliane A. da Silva ◽  
Carlos H. G. Martins ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Antibacterial Activity ◽  
Ethyl Acetate Extract ◽  
Phytopathogenic Fungus ◽  
Broth Microdilution ◽  
Actinomyces Naeslundii ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Almost All

Cercospora brachiata is a phytopathogenic fungus. To know more about the metabolites produced by this fungus, the objective of this work was to identify, isolate and characterize substances present in extracts of the growth broth and mycelium, using gas chromatography with mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). It was also objective to evaluate the antibacterial activity of the extracts. Among the compounds identified, fatty acids, esters, and steroids can be highlighted. The main compounds identified are 9-hexadecenoic, hexadecenoic, oleic, octadecanoic, lauric, myristic, palmitic, doceno-13-enoic, stearic, linoleic, and nonadecanoic acids present in almost all extracts. For the antibacterial activity, the broth microdilution method was used. The ethyl acetate extract of the mycelium presented inhibitory concentrations (MICs) against the bacterium Actinomyces naeslundii (100 μg mL−1) and Streptococcus sanguinis (200 μg mL−1). Finally, two steroids were isolated and identified in the hexane extract of mycelium: ergosta-6,22-dien-3β,5α,8α-triol and brassicasterol.

scholarly journals In vitro Antibacterial Activity of Libanotis montana Essential Oil in Combination with Conventional Antibiotics

2014 ◽  
Vol 9 (2) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Dragoljub L. Miladinović ◽  
Budimir S. Ilić ◽  
Tatjana M. Mihajilov-Krstev ◽  
Jovana L. Jović ◽  
Marija S. Marković
Keyword(s):  
Gas Chromatography ◽  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
Hierarchical Cluster ◽  
Gas Chromatography Mass Spectrometry ◽  
Bacterial Strains ◽  
Microdilution Method ◽  
Broth Microdilution Method

The chemical composition and antibacterial activity were examined of Libanotis montana Crantz subsp. leiocarpa (Heuff.) Soó. (Apiaceae) essential oil. Gas chromatography and gas chromatography/mass spectrometry were used to analyze the chemical composition of the oil. The antibacterial activity was investigated by the broth microdilution method against thirteen bacterial strains. The interactions of the essential oil and three standard antibiotics: tetracycline, streptomycin and chloramphenicol toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods: principal components analysis and hierarchical cluster analysis. Sesquiterpene hydrocarbons were the most abundant compound class in the oil (67.2%), with β-elemene (40.4%) as the major compound. The essential oil exhibited slight antibacterial activity against the tested bacterial strains in vitro, but the combinations L. montana oil-chloramphenicol and L. montana oil-tetracycline exhibited mostly either synergistic or additive interactions. These combinations reduced the minimum effective dose of the antibiotics and, consequently, minimized their adverse side effects. In contrast, the association of L. montana essential oil and streptomycin was characterized by strong antagonistic interactions against Escherichia coli ATCC 25922. In the PCA and HCA analyses, streptomycin stood out and formed a separate group.

scholarly journals Antibacterial evaluation of Styrax pohlii and isolated compounds

2013 ◽  
Vol 49 (4) ◽  
pp. 653-658 ◽  
Author(s):  
Camila Spereta Bertanha ◽  
Susane Hellen Utrera ◽  
Valéria Maria Melleiro Gimenez ◽  
Milton Groppo ◽  
Márcio Luis Andrade e Silva ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Concentration ◽  
Ethanolic Extract ◽  
Preliminary Evaluation ◽  
Microdilution Method ◽  
Aerial Parts ◽  
Broth Microdilution Method ◽  
Weak Antibacterial Activity ◽  
Mic Value

The antibacterial activity of the compounds egonol (1) and homoegonol (2), of the crude ethanolic extract of Styrax pohlii (Styracaceae) aerial parts (EE), and of its n-hexane (HF), EtOAc (EF), n-BuOH (BF), and hydromethanolic (HMF) fractions was evaluated against the following microorganisms: Streptococcus pneumoniae (ATCC 6305), S. pyogenes (ATCC 19615), Haemophilus influenzae (ATCC 10211), Pseudomonas aeruginosa (ATCC 27853), and Klebsiella pneumoniae (ATCC 10031). The broth microdilution method was used for determination of the minimum inhibitory concentration (MIC) during preliminary evaluation of antibacterial activity. The EE yielded MIC values of 400 µg/mL for S. pneumoniae and P. aeruginosa and 300 µg/mL for H. influenzae. The HF and EF fractions exhibited enhanced antibacterial activity, with MIC values of 200 µg/mL against S. pneumoniae, but only EF displayed activity against H. influenzae (MIC 200 µg/mL). The best MIC value with compounds 1 and 2 (400 µg/mL) was obtained for (1) against S. pneumoniae and P. aeruginosa. Therefore, 1 exhibited weak antibacterial activity against these standard strains.

Sign in / Sign up

Export Citation Format

Share Document